What happens in vagus: a case of recurrent paraganglioma with malignant transformation and an updated treatment algorithm†

Abstract

Paragangliomas (PGLs) are rare, extra-adrenal tumors, originating from neural crest cells and can occur anywhere from the skull base to the pelvic floor. Although these tumors are often benign, a fraction of malignant cases exist. Few isolated cases of malignant head and neck PGL are reported in the literature. Treatment algorithms rely heavily on retrospective case studies and institutional experience. We report an unusual case of an extensive, hereditary PGL, with invasive characteristics, that was refractory to radiation therapy. An operative approach was selected for recurrent disease in the setting of critical neurovascular structure compromise. Six months postoperatively, the patient was recovering as expected and had no evidence of recurrent disease. We propose a modified treatment algorithm based on an updated literature review that encompasses the spectrum of PGL, from benign and asymptomatic to invasive and malignant disease.

Figure 1:

Computed tomography, coronal view, shows multiple bilateral PGLs extending from the carotid bifurcations to the base of the skull, engulfing the vagus nerve.

Figure 2:

(A and B) Magnetic resonance images, coronal planes, highlight three of the four previously noted cervical PGLs decreasing in size, with the right inferior PGL remaining unchanged.

Figure 3:

(A and B) Magnetic resonance images, sagittal and coronal planes, show increased left-sided carotid PGL, with significant extension into the jugular foramen and skull base.

Figure 4:

Magnetic resonance angiogram, coronal plane, shows tumor compromise of the left internal carotid artery.

Figure 5:

CT of the head with contrast, transverse section demonstrating infiltration of left petrous and clivus regions of skull.

Figure 6:

Preoperative angiography shows intricate vascularity of the PGL.

Figure 7:

Representative CT image of the head shows postoperative changes associated with left temporal craniotomy and resection.

Figure 8:

PGL Treatment Algorithm. Major symptomatic criteria are complete cranial nerve palsy, progressive disease with impending threat to critical neurovascular structures, intracranial extension or recurrent disease refractory to other therapies. Minor symptomatic criteria are symptomatic disease in the absence of major symptomatic criteria (e.g. syncope). CT, computed tomography; MRI, magnetic resonance imaging; PGL, paraganglioma; SDH, succinate dehydrogenase; SRS, stereotactic radiosurgery. (Data from Lieberson et al. [6], Makeieff et al. [8], Fruhmann et al. [4], Patetsios et al. [5], Rao et al. [7] and Suarez et al. [9].)